The RCGP’s week-by-week guide to pregnancy (Emma’s Diary) advises that ‘a family with a history of nut allergy should avoid giving foods containing nuts until their baby is at least 3 years old’, but current thinking is exactly the opposite. Instead of restricting exposure to peanut protein during weaning, there is evidence that, rather than causing sensitisation, early exposure to peanuts may actually induce tolerance and prevent the abnormal immune response that causes an allergic reaction.
Several research publications in the last 10 years suggest that strict allergen avoidance (peanut, wheat, egg, and tree nuts) may not be an effective way of preventing the development of food allergy in high-risk families. Early life exposure may lead to tolerance not sensitisation, perhaps explaining why Jewish children in the UK have a prevalence of peanut allergy tenfold higher than those in Israel where peanut is used as a weaning food.1
While we are not quite ready to give large amounts of peanuts to children at high risk of developing nut allergy, international guidelines for primary prevention of food allergy have been recently updated to advise families to start weaning at 4 months, and to introduce complementary foods for all infants including those at high risk of developing allergic conditions due to parent and/ or older siblings with allergic disease.2
Food allergy is not yet fully understood, but in the interim we need to ensure that the advice we give to our patients is beneficial or neutral, but not potentially harmful.
- © British Journal of General Practice 2014
